Typical multi-pole automotive d.c. electric motors use bus bars to conduct current between the electrical connector of the motor and associated components such as chokes, capacitors, and brushes. Conventional bus bars have to be manufactured and physically attached, supported and connected with the motor. Typically, the bus bars are riveted to the brush card of the motor. The electrical connection is usually achieved using soldered or heat-fused joints.
Thus, there is a need to reduce the number of electrical connections required on the motor's brush card, to eliminate costly bus bars and to reduce the number of separate mechanical fasteners needed on the brush card.
Furthermore, conventionally, wound wire coils or chokes are installed close to the brushes of d.c. motors, particularly in automotive applications. The purpose of the chokes is to suppress radio-frequency interference (RFI) generated by the motor. Generally, the chokes are physically attached to the brush card of the motor using fixing or fastening techniques that require additional specific parts or processes, for example, the ends of the chokes may be soldered to conductors that are riveted to the brush card, and/or clips or other fasteners may be used to attached the chokes.
Another way of attaching chokes 10 to the brush card 12 is shown in FIG. 1. Connecting portions 14 of each choke 10 are inserted through an associated opening 16 in the brush card 12 and then the connecting portions 14 are bent to secure the choke to the brush card. Although no additional fasteners are used to attach this type of choke, additional bending steps are required which increases labor costs.
Hence, there is also a need to provide secure mechanical attachment of the choke to the brush card while avoiding the necessity specific fastening components or additional assembly procedures.